A constant selection pressure rewards a protein for performing well under one set of conditions. That can favor continuous activity even when the desired behavior is to switch on and off in response to a signal. Optovolution addresses this mismatch by making successful switching part of what cells must do to keep proliferating.
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6:50so she pioneered directed evolution. Here's the problem. Directed evolution is all about static selection pressure. For example, if I want to make an enzyme that breaks down a certain toxin, what I'm going to do is create a bacteria with these with these with this DNA that is constantly inside this toxin bath. >> Okay? So now only those bacteria that have the enzyme to break down the toxin are going to live. But naturally, what that means is that the enzyme is going to be constantly on. It's going to be constantly trying to break down that toxin. It's never going to turn off. >> So, it's going to this whole process of
7:32directed evolution is going to select >> for proteins that have continuous function, not dynamic function. >> That's very different from proteins that we see in life. >> Proteins are dynamic, >> right? >> They move from one configuration to the other. Here what we're seeing is a particular lian that green dot is moving in into the protein and the alpha helix in blue is changing shape. The protein is literally changing shape and toggling between one state and another state. And this is very natural for proteins to do. They want to toggle between an active and inactive conf confirmation in response to some kind of stimuli.
Molecular BiologyProtein EngineeringSynthetic BiologyBioengineering